Validity of the isotopic thermometer in central Antarctica: Limited impact of glacial precipitation seasonality and moisture origin

• Published in: Geophysical Research Letters
• Main Authors: Delaygue, Gilles, Jouzel, Jean, Masson, Valérie, Koster, Randal, Bard, Edouard
• Other Authors: Centre Européen de Recherche et d'Enseignement des Géosciences de l'Environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), NASA Goddard Space Flight Center (GSFC)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2000
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Antarctic; Greenland; The Antarctic; Antarc*; Antarctica
• Online Access: https://hal.science/hal-03103416; https://hal.science/hal-03103416/document; https://hal.science/hal-03103416/file/2000GL011530.pdf; https://doi.org/10.1029/2000GL011530

International audience The classical interpretation of water stable isotopes (deuterium or oxygen 18) retrieved from ice cores into past local temperature relies on the use of the spatial isotope/temperature slope as a surrogate of the temporal slope. Whereas this assumption has been challenged by independent methods in central Greenland, it is still considered as valid in central Antarctica. We use an atmospheric General Circulation Model (GCM) to study two parameters highlighted by previous studies as being among the most important with respect to this assumption. We show that in the GCM, between present-day and Last Glacial Maximum, the change in precipitation seasonality and the cooling of the moisture sources have limited and opposite effects on the isotopic record of the Antarctic local temperature. This conclusion strengthens the validity of the classical interpretation of isotope records in central Antarctica.